1. Field of the Invention
This invention relates to material handling machines and in particular to means for counterbalancing material handling machines.
2. Description of the Prior Art
In U.S. Pat. No. 3,998,342 of Jimmy D. Myers, one of the joint inventors herein, which patent is owned by the assignee hereof, an improved counterweight attachment means for loaders and the like is disclosed. As shown therein, the counterweight may be selectively mounted on the material handling structure carried on a pair of lift arms at the front of the machine. For this purpose, the counterweight is provided with hooking means adapted to engage a hook support carried on a bracket mounted to the bucket defining the material handling structure. Illustratively, the counterweight may then counterbalance the machine such as where a backhoe or the like is mounted to the rear end of the machine.
As further disclosed in said patent, the machine may comprise a tractor-type vehicle having an operator's station wherein the operator of the vehicle is provided with suitable controls for effecting the desired material handling operations. The controls may include means for lifting the bucket by means of the lift arms and, thus, the operator may control the pickup of the counterweight by the bracket on the bucket from the operator's station.
However, as disclosed in said patent, the hooking means on the counterweight is disposed at a relatively low elevation which makes the viewing of the hooking means by the operator at the operator's station relatively difficult because of portions of the apparatus interposed between the hooking portion of the counterweight and the operator. As shown in said patent, the hooking means on the counterweight is disposed slightly below the top of the weight portion of the counterweight which extends the full height thereof.
As further shown in said patent, the bucket defining the front material handling structure is provided with a bracket extending upwardly from the rear wall of the bucket so that the counterweight is effectively hung on the bracket substantially upwardly of the bucket in the picked-up position wherein the bucket effectively opens upwardly with the rear wall of the bucket being spaced substantially below the lower portion of the counterweight.
As further shown in said patent, the counterweight is adapted to be mounted selectively on the backhoe, which may comprise a second material handling structure and which may be removably installed on the rear end of the vehicle. Upon removal of the backhoe from the rear end of the vehicle, the counterweight may be installed on a second bracket means carried on the rear end of the vehicle so as to counterbalance the machine for use thereof as a conventional front loader or bulldozer. Thus, the counterweight may have a number of hooking portions selectively engageable with the different carrying means of the front material handling structure, the rear material handling structure, and the rear bracket carried by the rear end of the vehicle.